TULSA, Oklahoma - Thirty years ago this week, catastrophic floodwaters filled parts of south Tulsa, causing more than $60 million in damage. 

The City of Tulsa unveiled a new commemorative sign Monday at Cousins Park near 121st Street South and Yale Avenue that shows just how high the water got in that flood 30 years ago. 

The high water mark sign gives some perspective for just how high the water got 30 years ago when the Arkansas river crested at more than 25 feet. 

The National Weather Service says the Arkansas river is normally about six or seven feet high, and when it gets to 18 feet, that's when flooding begins. 

Tulsa mayor Dewey Bartlett along with the National Weather Service and the Army Corps of Engineers unveiled the sign October 3, 2016. 

They also talked about how technology has changed in the past three decades, and how much more prepared they are for any similar floods in the future. 

Meteorologist Steve Piltz with the NWS said the sign serves as an important reminder. 

"Well it kind of reminds us what happened and if you lose track of history then you're destined to repeat some of your mistakes, so always being aware of what can happen will help you prepare what's going to happen and we will have more challenges on the Arkansas river at some point," Piltz said. 

Bartlett also mentioned people can expect to start seeing changes to Cousins Park, which is funded by a $2 million bond issue passed three years ago by voters.